Superheater



July 7, 1942. 'r. o. SANDVIG SUPERHEATER 1 Filed Feb. 8, 1940 3 Sheets-Sheet l [Ill ulu m EEC E, gev-za, $422074;

ATTOR N EYS y 1942 T. o. SANDVIG 2,289,146

SUPERHEATER Fil ed Feb. .8, 1940 s Sheets-Sheet 2 g o l a El VENTOR ATTORN EYS July 7, 1942. T. o. SANDVIG SUPERHEATER 5 Sheets-Sheet 3 Filed Feb. 8, 1940 rfffllllllff/fflflf/l:

EJ621 74 54 72am ATTORNEYS Patented July 7, 1942 3 UNITED STATES PATENT OFFICE 2 Claims.

My invention relates to superheaters and has as one of the principal objects thereof the provision of a superheater so constructed and arranged whereby steam may be superheated to a suitable temperature and automatically controlled in accord with a selected temperature, thereby effecting an economy in operation of a steam generating apparatus to which the supe heater is connected.

Another object of my invention is to provide a superheater of the above described character which is simple in construction, durable in use, eflicient in operation and economical in manufacture.

Other objects and advantages will be apparent from the following description, appended claims and annexed drawings.

Referring to' the drawings wherein like reference characters designate like parts throughout the several views:

Figure 1 is a side elevation, partly in section, of my invention.

Figure 2 is a side elevation of the heater.

Figure 3 is an end elevation of the heater partly in section.

Figure 4 is a longitudinal sectional view of one of the burners.

Figure 5 is a vertical sectional view of the regulating valve,

Figure 6 is a detail sectional view taken on the line 6-45 of Figure 5.

Figure 7 is a vertical sectional view of the control valve and regulating device.

Figure 8 is a sectional View taken on the line 8-8 of Figure 7.

Figure 9 is an enlarged sectional view taken on the line 9-9 of Figure 1.

Figure 10 is a cross sectional view taken on the line |HJ of Figure 9.

Figure 11 is a cross sectional view taken on the line lll| of Figure 1.

Figure 12 is a fragmentary top plan view of the heater pipes and headers to which they are connected.

Figure 13 i a longitudinal sectional view of the lower or intake end of a modified form of coil assembly.

Figure 14 is a longitudinal sectional view of the upper or outlet end of the modified form of coil assembly.

Figure 15 is a sectional view taken on the line l-|5 of Figure 13.

Figure 16 is a sectional view taken on the line l6l6 of Figure 14.

Figure 17 is a vertical sectional View of a modified form of my invention.

Figure 18 is a vertical sectional view of the control valves and the regulating device utilized in connection with the modified form illustrated in Figure 17.

In practicing my invention, as illustrated in Figures 1 to 16 inclusive of the drawings, I provide a heater 5 formed with upper and lower sections 6 and 1 respectively, the latter being equipped with a plurality of transversely spaced gas burners 8 arranged through the front wall 9 of said heater. The outer or inlet ends 01. the burners 8 are connected to ends of fuel pipes H] for supplying fuel, for instance gas, to the burners. The opposite ends of the fuel pipes in are connected to a control valve ll hereinafter more fully described.

Arranged in the pipes H] are manually operable cut-off valves l2, the latter being disposed subjacent the burners 8 as clearly illustrated in Figure 1 of the drawings. The control valve II is connected to one end of a gas line I3, the opposite end of which is connected to a source of gas supply (not shown). Interposed in the line It is a regulating valve l4 and a T IS, the latter being connected to one end of a pilot lead 16, the opposite end of which is connected to a transversely disposed pilot header IT. A plurality of pilot pipes l8 have their lower ends connected to the header I! and their opposite ends extending through the front wall 9 of the heater and terminating in proximity and subjacent to the burners 8 whereby'to ignite the latter when the same is conditioned for operation. The line H; has interposed therein a cut-off" valve l9 whereby to control the flow or gas there. through. i

The upper section 6 of the heater 5 has disposed therein a coil assembly comprising a plurality of transversely spaced pipes 20, the latter being of a substantially S-shaped configuration having their lower runs disposed an appreciable distance above the burners 8 and connected to a transversely disposed header 2| arranged super- J'acent the burners 8 and postjacent the front wall 9. The upper or opposite ends of the pipes 20 are connected to a transversely disposed header 22 arranged prejacent the rear wall 23 of the heater and subjacent the top wall 24 thereof,

The header 2| has connected thereto one end of a steam pipe 25 which extends through the front wall 8, the opposite end of said pipe 25 being connected to a steam line 26, the latter being connected to a boiler or steam generating device (not shown). The header 22 is connected to the inner end of a steam supply pipe 21 extending through the rear wall 23, the opposite end of said pipe 21 being connected to a vertically disposed header 28 as clearly illustrated in Figure 1 of the drawings.

Without the heater 5 and adjacent the front wall 9 thereof, the pipe has interposed therein a reducing valve 29, the latter being equipped with a pipe 3| extending over the heater and connected to the pipe 21 whereby to control the steam entering the header 2| from the pipe 25 by the pressure in the pipe 21. The pipe 21 has also connected thereto one end of a pipe 32, the opposite end of which is equipped with a pressure gauge 33 whereby the pressure in the pipe 27 may be readily observed.

The upper wall of the valve II has extending therethrough the lower end of a plunger rod 34, the upper end of which is connected to a temperature regulating device for operating the valve II and which device 35 is hereinafter more fully described.

The control valve I I comprises a cylinder C in which the piston 36 is slidably mounted and said cyilnder is formed with spaced ports 31 arranged one above the other whereby downward and upward movement of the piston serves to successively close and open said ports respectively. The ports communicate with the rear ends of the pipes l9 whereby to control the flow of gas to the burners upon actuation of the piston. The lower section of the cylinder, subjacent the ports and pistons,.is connected to the supply pipe |3 as clearly illustrated in Figure '7 of the drawings whereby gas from said pipe I3 is supplied to the burners and under the control of the temperature regulating device 35, the latter being connected to the piston 35 by the piston rod 34 as heretofore set forth.

The temperature regulating device 35 comprises an inverted acetabular member 31 closed by a diaphragm 38 and in which is contained an expansible fluid 39, for instance mercury. The diaphragm 38 has connected thereto the upper end of the piston rod 34, the latter being slidably journaled through a bearing 48 carried on a plate 4| to which the cylinder is fixed.

Interposed between the diaphragm and bearing and sleeved about the piston rod 34 is a coil spring 42 coacting with the diaphragm 38 to urge the piston 36 upwardly within the cylinder C. The member 31 has connected thereto the lower end of a pipe 43, the upper end of which is connected to the pipe 21 as illustrated in Figure 1 of the drawings. Obviously, the temperature of the steam in the pipe 21 serves to operate the device 35 and thus control the operation of the burners 8 through the medium of the regulating valve The pipe 21 has also connected thereto the upper end of a pipe 44, the lower end of which is provided with a temperature gauge 45 whereby the temperature may be readily observed.

The regulating valve l4 comprises a cylinder 46 in which is mounted a spring pressed piston 41. Said cylinder is provided with a closed bottom 48 through which is slidably mounted a piston rod 49 extending through a packing gland 59. The lower end of the piston rod 49 is connected to a valve member 5| slidably mounted within a valve seat 52 formed in a valve casing 53, the latter being connected within the pipe line l3 as clearly illustrated in Figure 5 of the drawings. Between the piston 41 and the bottom 48, the valve casing communicates with the lower end of a pipe 54, the upper end of which is connected to they pipe 25 and has interposed therein a cut-off valve 55. Subjacent the cut-off valve 55, the pipe 54 is provided with a T 56 effecting communication with a by-pass pipe 51 connected to the pipe 25 and in which is located a cut-off valve 58.

Interposed in the pipe line 25, between the bypass pipe 51 and the pipe 54, is a cut-off valve 59. The steam line 26, which conveys moist steam to the header 2|, has connected therein a T 60, the latter being connected to one end of a by-pass line 6|, the opposite end of which is connected to the header or distributor 28. Said line 6| is provided with a pair of cut-01f valves 62 adjacent the T 69 and the header 28. Subadjacent the T 80, the steam line 26 is provided with a cut-oil valve 63. Obviously by closing the valve 63 and opening the valves 62 steam from the boiler is by-passed around the heater to the header 28 through the medium of the line 6|.

The header 28 has connected thereto a plurality of pipes 64, the latter being adapted for connection to various steam consuming apparatus, for instance an over 65 and vessel 66. Each of the pipes 64 is provided with a cut-off valve 61 adjacent the header 28. One or more of the pipes 64 may be provided with a section 68 having a smaller diameter than the respective pipe, as clearly illustrated in Figures 9, 10 and 11 of the drawings, whereby to build up the steam pressure passing therethrough. The lower end of the header 28 is provided with a valved water trap 69 for trapping the moisture in the header 28,

The upper or outlet ends of the tubes 29 adjacent the header 28 are tapered as at 10 to restrict the bores and thereby build up the pressure in said tubes. Each of the burners 8 comprises a nozzle 8a disposed within an elongated cylindrical shell 8b.

The shell 81) is fashioned about said nozzles 8a with perforations for the admittance of air within the shell and the rear end of the nozzles are connected to the pipes ID as clearly illustrated in Figure 4 of the drawings. It is to be understood that the cut-off valve l2 also serves as a regulating valve for controlling the flow of gas through the nozzles 8a.

In the modified form of heater illustrated in Figure 17 of the drawings I utilize a plurality of oil burners 80 in lieu of the gas burners disclosed in the preferred embodiment. Said oil burners are arranged in the same manner as the gas burners 8 and have connected thereto oil and air pipes 8| and 82. The oil and air pipes 8| and 82 are connected to oil and air control valves 83 and 84 respectively, said valves 83 and 84 being of a like construction as the control valve II in the preferred embodiment. The upper ends of the piston rods of the valves 83 and 84 are connected to a cross bar 85 with the latter being fixed to the lower end of a piston rod 85 of a temperature regulating device 81. The temperature regulating device 81 is of a like construction as the temperature regulating device 35 employed in the preferred embodiment and is connected by a pipe 88 to the steam outlet or supply pipe 89 efiecting connection between the tubes 99 in the heater and the header 9|, the latter operating in the same manner as the header 28 in the preferred embodiment.

A pair of regulating valves 92 and 93 are connected within the oil and air supply lines 94 and 95 respectively for controlling the passage of oil and air therethrough in the same manner as the valve I4 controls the supply of gas in the preferred embodiment. The oil and air line are connected to the oil and air control valves for supplying fuel to the burners 80. The valves 92 and 93 are connected to a pipe 96, the latter being connected to the steam supply pipe leading to the tubes in the same manner as the pipe 54 in the preferred embodiment.

In the operation of the apparatus, assuming the valves 62 at each end of the by-pass line 6| to be closed, for passage of the saturated steam from the generator outlet line 26 through the superheater, valves 63 and 58 are opened while valves 55 and 59 remain closed. This causes a flow of the saturated steam into the superheater supply line 25 and through the branch lines 51 and 54 into the chamber of valve I4 which results in elevation of the slide valve to open the fuel feed line I3 to the burners, the valves I2 also being open. As soon as the burners 8 commence operation by ignition through the pilot lights valves 59 and 5d are opened and valve 58 closed so that steam from the supply line 25 is caused to fiow through the superheater pipes 20 while steam pressure is maintained in the line 54 to retain the control valve I4 in open position. Should the superheated steam flowing through the outlet line 21 to the header 28 attain a predetermined maximum temperature the steam therein causes expansion of the fluid 39 of the regulating valve II to effect closure movement of the valve II to reduce the flow of fuel through the extension fuel feed lines I0 to the burners so as to reduce the heating temperature in the furnace of the superheater. When the pressure in the heater outlet line 21 reaches a predetermined maximum degree the regulating valve 29, connected with this outlet through conduit 3|, automatically reduces the pressure at the inlet of the superheater pipes. Should the flow of saturated steam to the superheater inlet be stopped, as by closure of either of the valves 63 or 59, the steam pressure to the control valve I4 is also cut off so that the spring action of this valve causes automatic closure of the fuel feed line I3 and stoppage of flow to the burners, providing means for positively preventing heating of the superheater pipes and injury thereto when the fiow of steam to these pipes has been stopped.

In the modified form of coil assembly illustrated in Figures 13 to 16 inclusive of the drawings I provide a plurality of both transversely and longitudinally spaced tubes I00 having their lower end sections IOI connected to the intake header I02 and their upper end sections I03 connected to the distributing header I04.

From the foregoing it will be apparent that I have provided a simple and efficient means whereby steam from a boiler may be superheated for distribution to various steam consuming devices, thereby lending to economical operation of the boiler.

Without further elaboration the foregoing will so fully explain the invention that others may,

by applying current knowledge, readily adapt the same for use under various conditions of service. Moreover, it is not indispensable that all the features of the invention be used conjointly since they may be employed advantageously in various combinations and sub-combinations.

It is obvious that the invention is not confined to the'herein described use therefor as it may be utilized for any purpose to which it is adaptable. It is therefore to be understood that the invention is not limited to the specific construction as illustrated and described, as the same is only illustrative of the principles of operation which are capable of extended application in advance forms, and that the invention comprehends all construction within the scope of the appended claims.

What I claim is:

1. In an apparatus of the character described, a superheater having heating burners therein, a fuel feed line to the said burners, a steam supply conduit connected to the inlet of the superheater, a valve for controlling the flow of fuel through the feed line, means for opening the said control valve by steam pressure from the supply line, means for automatically closing the fuel feed line when the flow of steam to the superheater inlet is stopped, a conduit connected with the outlet of the superheater, means for automatically regulating the pressure of the inlet in response to the pressure in the said outlet conduit, and means for automatically regulating the heating temperature of the superheater in response to the temperature of the steam in the outlet conduit.

2. An apparatus of the character described, a superheater having a burner therein, a fuel feed line to the said burner, a steam supply conduit connected to the inlet of the superheater, a valve for controlling the flow of steam from the supply conduit to the superheater, a valve in the said fuel feed line yieldingly held in closed position and operative by steam pressure to open the fuel line, a valve controlled auxiliary conduit connecting the fuel valve with the steam supply conduit at the discharge side of the steam supply control valve, and a valve controlled auxiliary conduit connecting the first mentioned aux-' iliary conduit with the steam supply conduit at the intake side of the steam supply control valve.

TALBERT O. SANDVIG. 

